Pancreaticoduodenectomy performed for a patient with prepancreatic postduodenal portal vein: a case report and literature review

Introduction

Prepancreatic postduodenal portal vein (PPPV) is a rare congenital variation, with only 17 cases reported in the literature and five of them undergoing pancreaticoduodenectomy (PD). Of these, four were L-shaped PPPV with a thin wall that was difficult to isolate, while only one normal-shaped PPPV was reported previously. For patients undergoing PD, recognizing this variation is important to prevent PPPV injury, which could lead to liver ischemia or intraoperative hemorrhage. We here present a case of normal-shaped PPPV who underwent PD.

Case presentation

A 68-year-old woman underwent PD for bile duct carcinoma at our hospital. Preoperative enhanced CT revealed that the portal vein was located anterior to the pancreas and posterior to the duodenum, and the L-shaped splenic vein was longitudinally located posterior to the pancreatic neck. During surgery, there was a loose tissue area between the PPPV and the pancreatic head, and the PPPV could be isolated safely. The morphology of PPPV was similar to normal portal vein. Due to the presence of the PPPV, a superior mesenteric artery (SMA)-first approach from the anterior was at high risk of vascular injury, and the pancreatic neck could not be dissected at the dorsal face of PV. Therefore, the SMA was revealed by the classic right posterior approach after transection of the pancreatic neck on the dorsal surface of L-shaped spleen vein, and the specimen was successfully resected without significant intraoperative bleeding. The patient was discharged 18 days after surgery without complications. The final pathology was bile duct carcinoma with R0 resection.

Conclusion

PPPV is a rare variant that can be diagnosed by preoperative imaging. In PD procedure, knowledge of PPPV helps in surgical decision-making, approach selection and avoid major bleeding due to PPPV injury. The origin of normal-shaped and L-shaped PPPV might be different. Normal-shaped PPPV can be safely isolated in this case.

Role of CT Imaging With Three-Dimensional Maximum Intensity Projection Reconstruction in the Evaluation of Portal Vein Variants at a Tertiary Care Hospital

INTRODUCTION

Portal vein (PV) is the principal blood vessel transporting blood from the alimentary tract and spleen to the liver. The aim of this study is to determine the prevalence of PV anatomical variations in our population using multidetector CT with maximum intensity projection (MIP) technique at a tertiary care hospital.

METHODS

This cross-sectional study was prospectively conducted from November 2018 to June 2019 in the Department of Radiology at a tertiary care hospital in Karachi. After informed consent, all the patients with no known hepatic pathology undergoing routine abdomen CT were included in this study. Patients with previous hepatic resection surgeries, undiagnosed large hepatic tumors/metastasis, and those with PV thrombosis were excluded.

RESULTS

A total of 500 patients (256 males and 244 females) were included in the study; the mean age of female patients was relatively higher as compared to the male patients (53.80 ± 18.44 vs. 44.15 ± 19.94 years; p = 0.000). Standard PV anatomy (type 1) was found in 438 patients (87.6%). Trifurcation (type 2) occurred in 18 patients (3.6%). Right posterior portal vein as the first branch of main PV (type 3) was found in 22 patients (4.4%). A separate branch of the right portal vein (RPV) to segment VII (type 4) and separate branch of the RPV to segment VI (type 5) were found in 6 (1.2%) and 16 (3.2%) patients, respectively.

CONCLUSION

Our study displayed a relatively higher frequency of standard PV anatomy (type 1) compared to previous studies. We highlight the role of MIP in the analysis of hepatic venous anatomy with its utility demonstrating improved detection of variations.